fix: prevent V8 turboshaft WASM Zone OOM during indexing (#298, #293)#322
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Large multi-language indexes crashed with `Fatal process out of memory: Zone` on Node 22/24 (including the bundled runtime) — V8's turboshaft optimizing WASM compiler exhausts its per-compilation Zone arena while compiling tree-sitter grammars on a background thread, even with tens of GB free (the Zone is a V8-internal arena, not the JS heap). Run node with V8 `--liftoff-only`, which keeps grammar compilation on the Liftoff baseline and never reaches the optimizing tier. Delivered via the bundled launcher + a one-shot CLI re-exec guard for all other launch paths. Empirically only `--liftoff-only` stops it (`--no-wasm-tier-up` / `--no-wasm-dynamic-tiering` do not), and it must be on node's command line (setFlagsFromString / worker execArgv / NODE_OPTIONS all fail). Reproduced the exact crash with the real indexer on Node 24.16 against a 2,880-file / 18-language repo and confirmed the fix eliminates it; full suite + 7 new tests pass. Bumps to 0.9.4. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Fixes the
Fatal process out of memory: Zonecrash that abortscodegraph index/codegraph initpartway through parsing large multi-language repos on Node 22 and 24 — including CodeGraph's own bundled Node 24 runtime. Resolves #298 and #293.Root cause
Not a system OOM. V8's "turboshaft" optimizing WASM compiler exhausts its per-compilation Zone arena (a V8-internal arena, not the JS heap) while compiling tree-sitter's large WebAssembly grammars on a background thread — so it fires with tens of GB of RAM free. Stack:
Zone::Expand → turboshaft::…WasmLoweringPhase → GenerateWasmCode → BackgroundCompileJob::Run.Fix
Run node with V8's
--liftoff-only, keeping grammar compilation on the Liftoff baseline so it never reaches the optimizing tier. Delivered two ways:scripts/build-bundle.sh) and the Windows npm-shim pass the flag directly (zero overhead for installed users), andnpx, a globally linked dev build).The flag must be on node's command line —
setFlagsFromString, workerexecArgv, andNODE_OPTIONSall fail to apply it (verified). And empirically--no-wasm-tier-up/--no-wasm-dynamic-tieringdo not prevent the crash; only--liftoff-onlydoes.Validation
Reproduced the exact issue stack with the real indexer on the shipped Node 24.16 runtime against a generated 2,880-file / 18-language repo, then confirmed the fix:
codegraph index, Node 24.16)Fatal process out of memory: Zone--no-wasm-tier-up/--no-wasm-dynamic-tiering--liftoff-only(the fix)A/B on the same fixed build toggling only the guard:
CODEGRAPH_NO_RELAUNCH=1→ 💥 crash; normal → ✅. MCP server verified working through the re-exec. Full suite (737) + 7 new tests pass.🤖 Generated with Claude Code